Whether a continuity correction (1/2.) should be taken into
account. Default is True.

Returns :

u : float

The Mann-Whitney statistics.

prob : float

One-sided p-value assuming a asymptotic normal distribution.

Notes

Use only when the number of observation in each sample is > 20 and
you have 2 independent samples of ranks. Mann-Whitney U is
significant if the u-obtained is LESS THAN or equal to the critical
value of U.

This test corrects for ties and by default uses a continuity correction.
The reported p-value is for a one-sided hypothesis, to get the two-sided
p-value multiply the returned p-value by 2.